Gendron, V. 1961. The Dragon Tree. A Life of Alexander, Baron von Humboldt (Longmans, Green, New York, NY).
Humboldt, A. v. 1849. Aspects of Nature in Different Lands and Different Climates (Longman, London).
Humboldt, A. v. 1995. Personal Narrative of a Journey to the Equinoctal Regions of the New Continent (Penguin, London).
Raby, P. 2001. Alfred Russel Wallace (Chatto & Windus, London).
Wallace, A. R. 1969. Natural Selection and Tropical Nature. Essays on Descriptive and Theoretical Biology (Gregg International, Farnborough, England).
Wallace, A. R. 1980. My Life (Chapman & Hall, London).
Willdenow, C. L. 1805. The Principles of Botany, and of Vegetable Physiology. Translated from German (Edinburgh, 1805).
Willig, M. R., et al. 2003. Latitudinal gradients of biodiversity: Pattern, process, scale, and synthesis. Annual Review of Ecology and Systematics 34:273–309.
Ginzburg, L., and M. Colyvan. 2004. Ecological Orbits: How Planets Move and Populations Grow (Oxford University Press, Oxford).
Gittleman, J. L., and A. Purvis. 1998. Body size and species-richness in carnivores and primates. Proceedings of the Royal Society London B 265:113–119.
Kant, I. 1987. Critique of Judgement (Hackett, Indianapolis, IN).
Lawton, J. H. 1999. Are there general laws in ecology? Oikos 84:179–192.
May, R. M. 1999. Unanswered questions in ecology. Philosophical Transactions of the Royal Society London B 354:1951–1959.
Murray, B. G. 2001. Are ecological and evolutionary theories scientific? Biological Reviews 76:255–289.
Nee, S. 2004. More than meets the eye. Nature 429:804–805.
Simberloff, D. 2004. Community ecology: Is it time to move on? American Naturalist 163:787–799.
Slobodkin, L. B. 2001. The good, the bad and the reified. Evolutionary Ecology Research 3:1–13.
Thomas, C. D., et al. 2004. Extinction and climate change. Nature 427:145–148.
Whitfield, J. 2005. Biogeography: Is everything everywhere? Science 310:960–961.